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FormatAbstract.md

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+The `FormatAbstract` class implements the [`FormatInterface`](FormatInterface) interface with basic functional behavior and adds common helper functions for new formats:
+
+* [setCharset](#the-setcharset-function)
+* [getCharset](#the-getcharset-function)
+* [setContentType](#the-setcontenttype-function)
+* [callContentType](#the-callcontenttype-function)
+* [getItems](#the-getitems-function)
+* [setExtraInfos](#the-setextrainfos-function)
+* [getExtraInfos](#the-getextrainfos-function)
+* [sanitizeHtml](#the-sanitizehtml-function)
+* [array_trim](#the-array_trim-function)
+
+#Functions
+
+#The `setCharset` function
+
+The `setCharset` function receives the character set value as string and returns the object instance.
+
+```PHP
+setCharset(string): self
+```
+
+#The `getCharset` function
+
+The `getCharset` function returns the character set value.
+
+```PHP
+getCharset(): string
+```
+
+#The `setContentType` function
+
+The `setContentType` function receives a string defining the content type for the HTML header and must return the object instance.
+
+```PHP
+setContentType(string): self
+```
+
+#The `callContentType` function
+
+The `callContentType` function applies the content type to the header data and must return the object instance.
+
+```PHP
+callContentType(): self
+```
+
+#The `getItems` function
+
+The `getItems` function returns the items previously set by the [`setItems`](FormatInterface#the-setitems-function) function. If no items where set previously this function returns an error.
+
+```PHP
+getItems(): array
+```
+
+#The `setExtraInfos` function
+
+The `setExtraInfos` function receives an array of elements with additional information to generate format outputs and must return the object instance.
+
+```PHP
+setExtraInfos(array $infos): self
+```
+
+Currently supported information are:
+
+Name | Description
+-----|------------
+`name` | Defines the name as generated by the bridge
+`uri` | Defines the URI of the feed as generated by the bridge
+
+#The `getExtraInfos` function
+
+The `getExtraInfos` function returns the information previously set via the [`setExtraInfos`](#the-setextrainfos-function) function.
+
+```PHP
+getExtraInfos(): array
+```
+
+#The `sanitizeHtml` function
+
+The `sanitizeHtml` function receives an HTML formatted string and returns the string with disabled `<script>`, `<iframe>` and `<link>` tags.
+
+```PHP
+sanitizeHtml(string $html): string
+```
+
+#The `array_trim` function
+
+The `array_trim` function receives an array of strings and returns the same array with all elements trimmed (like using the `trim` function on all elements)
+
+```PHP
+array_trim(array $elements): array
+```